Geneva: US Secretary of State John Kerry arrived in Geneva on Thursday to test the seriousness of a Russian proposal to secure Syria's chemical weapons. Kerry and a team of US experts will have at least two days of meetings with their Russian counterparts on Thursday and Friday.

They hope to emerge with an outline of how some 1,000 tons of chemical weapons stocks and precursor materials as well as potential delivery systems can be safely inventoried and isolated under international control in an active war zone and then destroyed.

Officials with Kerry said they would be looking for a rapid agreement on principles for the process with Russians, including a demand for a speedy Syrian accounting of their stockpiles. One official said the task is "doable but difficult and complicated."

The official said the US is looking for signs of Russian seriousness and thinks it will know in a relatively short time if the Russians are trying to stall. Another official described the ideas that the Russians have presented so far as "an opening position" that needs a lot of work and input from technical experts.

The US team includes officials who worked on inspection and removal of unconventional weapons from Libya after 2003 and in Iraq after the first Gulf War. The officials, who spoke on condition of anonymity because they were not authorised to speak publicly on the sensitive negotiations, said the teams that eventually go into Syria to do the work would have to have an international mix, as would their security.

Kerry planned to meet with Lakhdar Brahimi, the UN-Arab League envoy for Syria, before sitting down with Lavrov. The hastily arranged meeting in Geneva comes as the White House tries to pin success or failure of the diplomatic track on Russia's willingness to take a tough line with its ally Syria.

Syrian rebels, however, are disappointed at best in President Barack Obama's decision to forgo a military strike in favour of an agreement to take access to chemical weapons away from President Bashar Assad. At the same time, the CIA has begun delivering light weapons and other munitions to the rebels over the past two weeks, along with separate deliveries by the State Department of vehicles and other gear, The Washington Post reported late on Wednesday.

The deliveries have lagged, the newspaper said, because of logistical challenges and US fears that any assistance could wind up in the hands of extremists. Some US lawmakers have chided the administration, which said months ago it would send lethal aid, for not moving more quickly to help the rebels.

Obama also found opposition in Congress to putting on hold his request for authorisation to punish Assad militarily for his government's alleged role in a chemical attack on Damascus suburbs in August 2013. His Russian counterpart, Vladimir Putin, asserted in an opinion piece in The New York Times, that a potential strike by the US would create more victims and could spread the conflict beyond Syria and unleash a new wave of terrorism.

In meetings planned for later on Thursday and again on Friday with Russian Foreign Minister Sergey Lavrov, Kerry will prod Moscow to put forward a credible and verifiable plan to inventory, quarantine and destroy Syria's chemical weapons stocks, according to US officials.

Kerry is accompanied by American chemical weapons experts to look at and possibly expand on Russian ideas for the complex task of safely dealing with the vast stockpiles in the midst of a brutal and unpredictable conflict. Russian technical experts will join Lavrov in the meetings.

"Our goal here is to test the seriousness of this proposal, to talk about the specifics of how this would get done, what are the mechanics of identifying, verifying, securing and ultimately destroying the chemical weapons," State Department spokeswoman Jen Psaki said shortly before Kerry left Washington.

The US is hoping that an acceptable agreement with the Russians can be part of a binding new UN Security Council resolution being negotiated that would hold Syria accountable for using chemical weapons. Russia, however, has long opposed UN action on Syria, vetoed three earlier resolutions, blocked numerous, less severe condemnations and has not indicated it is willing to go along with one now.

A senior UN diplomat, speaking on condition of anonymity because contacts have been private, said Thursday's meeting will be an exploratory session to gauge whether they can embark on "the herculean task" of dismantling Syria's chemical weapons while the country is at war.

In his column posted on Wednesday on the Times website, Putin asserted that it is "alarming" that military intervention in internal conflicts in foreign countries "has become commonplace for the United States."

"Is it in America's long-term interest? I doubt it," Putin wrote. "Millions around the world increasingly see America not as a model of democracy but as relying solely on brute force, cobbling coalitions together under the slogan 'you're either with us or against us.'"

Putin said he favoured taking advantage of Syria's willingness to place its chemical arsenal under international control and welcomed Obama's interest in continuing to discuss Syria with Russia.